Stoker-furnace



Patented Jan. 17, 1922.

J. B. LEONARD AND J. F. DIRZUWEIT.

STOKEH FURNACE.

APPLICATION FILED 1AN.2,1920.

1'. i LEONARD AND 1. F. DrRzuwE-IT.

STOKEH FURNACE. y APPLICATION' man JAN. 2. rezo.

1,403,609. PatentedJan. 17, 1922.

4 SHEETS-SHEET 2.

Snom/toa Jak/z5 leonard, Ja/z/zjf @ttm/M m J. B. LEONARD AND1. F.DIRZUWEIT.

STOKER FURNACE.

APPLlcATIoN man 1AN.2,1920.

Patented Jan. 17, 1922.

4 SHLE fS--SHEET 3.

m w m m J. B. LEONARD AND J. F. DIRZUWEIT.

sToKER FufmAcE. APPLCATIGN FILED JAN. 2, 1920. 1,403,609. Patented Jail.17, 1922.

4 SHEETS-Sgen 4.

Elf/tom m UNITED STATES PATENT OFFICE.

JOHN BIRCH LEONARD A ND JOHN F. DIRZUWEIT, OF BALTIMORE, MARYLANDASSIGNORS, BY MESNE ASSIGNMENTS, TO LEONARD ENGINEERING COMPANY,

A CORPORATION OF MARYLAND.

STOKER-FURNACE.

Specification of Letters Patent.

Patented Jan. 17, 1922..

Application led January 2, 1920. Serial No. 348,762.

T o all whom t may conce/rn:

Beit known that we, JOHN BIRCH LEONARD and JOHN F DnzzUwEIT, citizens ofthe United States, residing in the city of Baltimore and State ofMaryland, have invented certain new and useful Improvements inStoker-Furnaces, of which the following is a specification.

This invention relates to improvements in stoker furnaces.

An important object of the invention is to provide an eiiicient furnacewherein comminuted fuel may be used.

A further object is to provide an automatic furnace which is simple inconstruction, cheap to manufacture and the parts of which are readilyreplaced when destroyedby prolonged use.

Other objects and advantages will be apparent throughout the course ofthe following description.

In the accompanying drawings wherein for the purpose of illustration isshown a preferred embodiment of our invention and wherein like referencecharacters designate like parts throughout,

Figure 1 is a sectional view taken through. a furnace embodying ourinvention taken o n line 1 1 of Figure 2,

Figure 2 is a frontk elevation thereof,

Figure 3 is a section taken on the line 3-3 of Flgure 1,

Figure 4 is a section taken on the line 4.-4. of Figure l,

Figure 5 is a rear elevation of one of the twver boxes,

igure is a plan View thereof;

Figure 7 is a'section taken on the line 7-7 of Figure 6,

Figure 8 is an enlarged detail view showing the link connection,

Figure 9 is a rear elevation of a pusher bar,

Figure 10 is a section taken on the line 10-10 of Figure 9, and

Figure 11 is a perspective view of a portion of the-operating shafts andassociated. elements.

Referrin now more particularly to the drawin s t e numeral 10 indicatesa furnace as a w ole having therein the usual steam and Water drums.

The lower portion of the furnace is divided into a fire box 1'1 and' an'ash pi 12 by a step, like arrangement of twyer boxes 13. In the presentillustration wherein the furnace 1s shown as embodying two series oftwyer boxes the outer ends of the twyer boxes are embedded in the sidewalls 14 of the furnace and the innerv ends rest upon a centralsupporting wall 15.

Each. of the twyer boxes 13 comprises a rectangular box-like structure16 provided upon its rear face, or that face which when the twyer box isin its proper position faces the rear of the furnace with a longitudinalwater chamber 17. This water chamber 17 projects beyond lthe normal rearWall of the box like structure ,16 and has a depth of approximatelyone-half of thelepth of the twyer box proper. At each end the Waterchamber 17 is provided with a vertical opening which receives an inletpipe 18 and a horizontal rearwardly extending opening Which receives anOutlet pipe 19. The inlet pipes 18 of the uppermost of the twyer box ofeach series are connected with any suitable source of Water supply andthe outlet pipes 19 of the lowermost twyer box of each series form thefeed water supply pipes for the furnace. Each of the water chambers 17is provided upon the rear of its upper surface with an upstandingfridge20, the top of which lies in the same plane as the top of the twyer boxproper. This ridge is provided with spaced air outlet openings 21. y

The ends of the twyer boxes are provided with horizontal flanges 22braced by vertical flanges 23. In placing the twyer boxes in position atthe ends of the twyer boxes which enter the side wall of the furnace,the flanges 22 and 23 are embedded' in the Wall while at the ends whichengage the supporting wall the flanges 22 .rest upon the supporting Walland the flanges 23 are embedded therein. The rear faces of the twyerboxes below the Water chambers 17'are provided With spaced air outletopenings'24..

In the front and rear Walls of each of the tWyer boxes are arrangedalined pairs of bearings 25 and 26 for a purpose 'hereinafter to appear.The rear Wall of the twyer box extends downwardly as at 27 below thebottom level ofthe twyer box proper and is provided with ash outletopenings 28, the urpose -of which will presently appear. Elpon' itsfront' face the twyer box4 1s pr vided with spaced pairs of ears 29having formed in their upper surface notches 29', spaced from the frontwall of the twyer box, which are adapted to receive the dependingportion 27 formed on the rear face of thel twyer box next above. It willbe obvious that between the rear wall of one twyer box and the frontwall of the twyer box nextbelow a space 30 is formed as clearly shown inFigure 3. 'The ears 29 have formed therein openings 31 for a purposepresently to appear.

The bottom of each twyer box is provided with a circular dependingflange 32 adapted to receive the upper end of a branch pipe 33 whichcommunicates with a conduit 34 through which is forced air underpressure. Mounted upon the upper faces of the twyer boxes are plates 35,having openings z36 formed therein to allow the passage ofV air. The twoend plates of each twyer box are provided with openings for thereception of the inlet pipes 18 and are held in position by these pipes.The remaining plates may be held in position in any desired manner asfor example by means of lugs 37 formed upon the bottoms of the plates 35and abutting the shoulders 20 formed upon the water chambers 17 Mountedupon the front wall of the furnace are hoppers 38 having offsets 39,forming ockets 40. The bottom of each pocket 40 1s ormed by a dead plate41 which is flush with the top ofthe uppermost twyer box 13. Slidablymounted in the pockets 40 and in the pockets formed by the overhangingwater chambers 17 are `pusher bars 42. Each pusherbar comprises avertical portion 43 and a horizontal portion 44 integral with and ofgreater width than the vertical portion 43. Formed in the pusher barsare air outlet openings 45.

Secured to the pusher bars 42 are push rods 46. Each of the rear ends ofthe push rods 46 has secured thereto in any suitable manner a bifurcatedmember 47 which carries the pin'48. These pins operate in slots 49formed in levers 50 which are pivotally connected to the ears 29 bymeans of pins 51 extending through the openings 31 thereof. The pushrods of the pusher bars 42 which are mounted in the pockets .40 extendthrough openings 52 formed in the walls of the ockets. Secured to thehopper in any desirable manner are supporting arms 53 to which thelevers 50 which connect with the push rods 46 of the pusher bars arepivoted. Bars 54 extend through slots 55 formed in the front wall of theash pit 12 and are pivotally connected to the levers'50. The bars 54 areprovided within the furnace with arms 56.

Connecting rods 58 extend through slots 57 formed in the wall of thefurnace and are pivotally connected with the arms 56. These connectingrodi have their opposite ends pivotally connected Iwith cranks 59 formedon a shaft 60 journaled in suitable brackets 61. This shaft bears apinion 62. A power shaft 63 is provided having thereon a segmental gear64 having a sufiicient number of teeth as at 65 to cause the pinion 62to perform a complete revolution at each engagement of thel teeth 65therewith. This power shaft 63 is driven at a low rate of speed by anysuitable prime mover 66.

Secured to the bridge wall of the furnace below the lowermost twyer boxare brackets 67 having rotatably mounted therein shafts 68. Supports 69are secured to the shafts 68 and carry dumping grates 70 havingfairopenings 71 formed therein. Secured to the rear face of each lowermosttwyer box is a defiecting plate 7 2 having air openings 73 formedtherein. Each deiecting plate has its lower edge arranged adjacent tothe upper edge of the corresponding dumpin grate 70. An arm 74 issecuredto eac shaft 68 and is pivotally connected with one end of aconnecting rod 7 5. The opposite end of each link 75 is pivotallyconnected with the inner end of a connecting rod 75. The outer end ofeach link 75 is pivotally connected with a crank 76 formed on a shaft77, also mounted in bearings formed in the brackets 61. This shaft 77 isprovided with a pinion 78 of the same size as the. pinion 62 and adaptedto engage the teeth 65 of the gear 64. The connecting rods1 75 may besupported by links 79 pivoted to the ears 29 of the lowermost twyerboxes 13.

The operation of our furnace is as follows:

Fuel is fed from the hopper 38 and moved by the pusher bar 42 adjacentthe bottom thereof outwardly upon the uppermost of the twyer boxes 13where the fuel is up-v plied with air for combustion. As the m vement ofthe fuel continues the fuel from the uppermost twyer box passesdownwardly upon the second of the twyers and so on downwardly until it*arrives upon the dumping grate 70. Here the fuel is almost if notentirely consumed, and supplied with sufficient air to prevent any lossof fuel. The operation of the ash support dumps the ashes periodicallyinto the ash pit 12.

In event of any ash passing back of the pusher bars 42, this ash ispassed downwardly into the pit through the openings 30 and through theopenings 28l formed in the rear face of the twyer boxes. Air forcombustion is also supplied to the fuel through the openings 24 formedin the rear faces of the twyer boxes and the openings 45 formed in thepusher bars.

The fuel in its downward passage heats the water in the water chambers17. These water chambers have therefore a double function, that ofheating the water for supply to the boiler and that of cooling the rearend of the twyer box to prevent burn- I ing out thereof by the flames.In order that the flame may be more fully directed against the steam andwater drums of the furnace and that combustion may be complete we haveprovided a coking arch 80 to assist in the combustion and a deflectingarch 8l which tends to direct the flames upwardly against these drums.

It is to be understood that the form of our invention herewith shown anddescribed is to be takenl as a preferred example of the same, and thatvarious changes in the shape, size, and arrangement of arts may be madewithout departing from t ie spirit of the invention or the scope of thesubjoined claims.

lVliat we claim is:

l. In a furnace, a fuel support comprising a plurality of twyer boxesarranged in stepped formation, each of said twyer boxes including a rearwall, said twyer boxes being provided with extensions projectingrearwardly of the rear walls of the twyer boxes to form recesses, meanscarried by each of said twyer boxes upon the front face thereof forsupporting the rear end of the next upper twyer box, pusher barsnormally disposed within said recesses, and means for actuating saidpusher bars.

2. In a furnace, a fuel support compris ing a plurality of twyer boxesarranged in stepped fonmation, each of said twyer boxes including a rearface, said twyer boxesbeing provided upon` their rear faces adjacent theupper edges thereof with water chambers, comprising longitudinallyextending portions projecting rearwardly of the rear walls of the twyerboxes, said water chambers overhanging the next lower twyer boxes andformin therewith recesses, pusher bars normally disposed within therecesses, and means for periodically actuating saidpusher bars.

3. In a furnace, a fuel support comprising a' plurality of twyer boxesyarranged in stepped formation, each of said boxes being provided uponits rear face adjacent the upper edge thereof with a water chambercomprising avlongitudinally extending portion overhanging the next lowertwyer box and forming therewith a recess, said water chambers beingconnected in series, pusher bars normally disposed within the recessesfor assisting in the rearward motion yof the fuel bed, and means foractuating said pusher bars.

4. In a furnace, a fuel support comprising a" plurality of twyer boxesarranged in stepped formation, a plurality of series of pusher rodsslidably mounted in said twyer boxes, pusher bars secured to said rods,a plurality of series of levers pivotally connected with said twyerboxes, said pusher rods .being pivotally connected to said leversintermedlate the ends thereof, bars connecting the lower ends of thelevers' of each series, a crank-shaft, a pinion mounted on saidcrank-shaft, cranks carried by said crank-shaft, connectin rodspivotally connected with said cran sand said bars, a grate pivotallyImounted rearwardly ofthe lowermos't twyer box, rocker arms connectedwith said ion mounted on said last named shaft, cranks carried by saidlast named shaft, means pivotally connected with said last named cranksand said rocker arms for dumping said grate, a third shaft, a mutilatedgear mounted upon said last nanied shaft and adapted to mesh with saidpinions, and means for rotating said last named shaft. l

In testimony whereof we aflix our signatures. A

JOHN F. DIRZUWEIT.

grate, a second crank-shaft, a pin- JOHN BIRCH LEONARD. l

